New FILEPKG command: INITVARS

[KAPLAN.PA]

I have added a new filepkg command to the system.  It is already
included in BYTE.SAV and ABC, and will appear in any D loadups made
Friday or after.

INITVARS is used for initializing variables--setting their values only
when they are currently NOBIND.  A variable value defined in an
INITVARS command will not clobber the current value.  This means that
re-loading files to work on some aspect will not change the variable values.

The format of an INITVARS command is just like VARS.  The only difference is
that atomic elements in the argument of the command will not cause the
current core value to be dumped; instead they will define NIL as the
initialization value.

Thus, (INITVARS FOO (FUM 2)) is the same as (INITVARS (FOO NIL)(FUM 2)).

INITVARS should be used instead of VARS for almost all variables in system
files.  It also should be used instead of (ADDVARS (FOO)) when the purpose
is merely to insure that the value is NIL.

INITVARS puts out an RPAQ? command on the file instead of RPAQ.  This is
a new function that I also added to the system, and which should also
be documented.

--Ron